The dominance of Amazon's range of Kindles and the growing smartphone, tablet and so-called phablet market have made it hard for Sony's suite of e-readers and rivals like Nook to carve out a niche for themselves. According to The Bookseller, Amazon has around 90% of the dedicated e-reader market in the UK.

Canadian firm Kobo was bought by Japanese e-commerce company Rakuten, which is looking to grow its business globally in a bid to challenge Amazon.

The global market in dedicated e-readers peaked in 2011 with 23 million devices sold, but is expected to fall to 10 million by 2017 as phones and tablets eat into the overall market, according to the research consultancy Gartner.

Still, the sale of printed books will be outstripped by e-books by 2018, a report by Pricewaterhouse Coopers suggested.